Pump



0. KUEHNE April 13, 1937.

PUMP

Filed June 29, 1934 Oscar [(uehn e INVEN TOR.

ATTORNEY.

Patented Apr. 13, 1937 UNITED STATES PATENT OFFICE 11 Claims.

This invention relates generally to pumps, and specifically to pumps forpumping abrasive or corrosive fluids.

It has for its general object the provision of new and improved meanswhereby the fluid is kept out of contact with the relatively movableparts of the pump, such as the piston, rods and bearings therefor.

A specific object of the invention is to provide a double acting pump soconstructed that the use of stufling boxes and piston rods working.

therethrough is rendered unnecessary, and the fluid is efficientlyprevented from entering between the piston and its bearing.

Other objects will hereinafter appear.

' The preferred embodiments of the invention are illustrated by theaccompanying drawing, wherein Fig. l is a sectional elevation of thepump; Fig. 2, a diagrammatic top plan view of the plunger andreciprocating parts; Fig. 3, a detail view of the protective member, andFig. 4, a detail view of another embodiment of the protective member.

The pump has a pair of chambers l and 2, the former having inlet andoutlet valves 3 and 4, and the latter having inlet and outlet valves 5and 6. Fluid enters the chambers and 2 through the inlet valves 3 and 5from a common intake 1, and passes from the chambers and 2 through theoutlet valves 4 and 6 into the common outlet 8. Reciprocable in thebearing 9 and extendin into the chambers and 2 is the piston In. On thatend of the piston '|0 projecting into the chamber 2 is an elasticcup-shaped protective member having an external annular flange l2 sealedto the wall of the chamber 2 adjacent to the bearing 9 by the ring I3;and on that end of the piston l9 projecting into the chamber is a likeprotective member |4 having an external annular flange l5 sealed to thewall of the chamber adjacent to the bearing 9 by the ring The members IIand H are at all times taut on the piston ID.

The piston I9 is reciprocated by the cross bars |1 (Fig. 2) connectedthereto between the members II and I4 and extending outwardly throughelongated openings l8 in bearing 9 to push rods l9 which are connectedby the cross member 29 to the cross head 2|, the cross head 2| beingactuated by conventional means. If desired, suitable guides 22 may beprovided for the guidance of the push rods l9.

The operation of the pump is as follows: when the piston moves from theposition shown tion, the inlet valve 5 closes, the outlet valve 6'opens, and the fluid in chamber 2 is expelled therefrom through outletvalve 6 and outlet 8. Simultaneously, the outlet valve 4 closes, theinlet valve 3 opens, and a fresh charge of fluid is drawn from inlet 1through inlet valve 3 into chamber I.

When the piston I moves from its dotted line position into its solidline position, the inlet valve 3 closes, the outlet valve 4 opens, andthe fluid in chamber I is expelled through outlet valve 4 and outlet 8.Simultaneously, the outlet valve 6 closes, the inlet valve opens, and afresh charge of fluid is drawn from inlet I through inlet valve 5 intothe chamber 2.

As the piston reciprocates the fluid is alternately drawn into andexpelled from the chambers I and 2 in the manner above set forth.

It will be obvious that the use of conventional piston rods and theirstufiing boxes, and the well known trouble incident thereto, areeliminated, and that the members II and I4 effectively prevent theentrance of foreign matter in the fluid between the piston lll andbearing 9, so that abrasion and corrosion of the piston .and its bearingare thereby prevented.

As the members H and 4 are elastic (preferably rubber) I theyautomatically expand and contract as the piston Ill reciprocates,remaining taut at all times thereon. As eachend of the piston I0withdraws from its chamber, the friction between the periphery of thepiston adjacent said end and the elastic member thereon incident to suchwithdrawal is reduced because such movement tends to create a vacuum inthe chamber which has a tendency to pull the elastic member away fromthe same during such withdrawal, as indicated by dotted lines in Fig. 4.

The power required to operate the conventional plunger pump is excessiveon account of the great amount of packing required to seal it, whereasin the present construction packings are eliminated.

The members II and I4 may be as shown by Fig. 3, or as shown by Fig. 4.In Fig. 3, the member 39 is substantially cup-shaped to receive thepiston I9, and has the annular flange 3| adjacent its rim and projectingoutwardly to be held in place against the wall 33 by the ring 32. InFig. 4, the construction is the same, except that the bottom of the cup34 is open as indicated at 35, but is held snugly in sealing engagementwith the end of the piston by plate 36. The ring 32 may be held in placeon the wall of the chamber by screws 31 and the plate 36 may bepositively held in position to hold the bottom of the cup 34 snuglyagainst the piston by suitable holdfast means 38.

5 Various advantages oi. the invention, changes in construction, and newuses other than as hereinabove set forth will be apparent to thoseskilled in the art.

I claim: 3 ['1] 1. A pump having a. pair 01' chambers; an in-' let valveand an outlet valve for each of said chambers; a bearing between saidchambers; a piston reciprocable in said bearing and extending into saidchambers; elastic cup-shaped mem- 15 bers sealed to the walls of saidchambers and taut on and enclosing the ends of said pistons to seal saidends from said chambers; and reciprocating means extending into saidbearing and connected to said piston between said members.

2. A pump having a pair of chambers; an inlet valve and an outlet valvefor each of said chambers; a bearing between said chambers; a pistonreciprocable in said bearing and extending into said chambers; means toseal the ends of said 25 piston from said chambers; and reciprocatingmeans extending into said bearing and connected to said piston betweensaid sealing means.

3. A pump having a pair of chambers; an inlet valve and an outlet valvefor each of said 30 chambers; a bearing between said chambers; a pistonmovable in said bearing and extending into said chambers; means to sealthe ends of said piston from saidchambers; and piston actuating meansconnected to said piston between 35 said sealing means.

4. A pump having a pair of chambers; an inlet valve and an outlet valvefor each of said chambers; a bearing between said chambers; a pistonreciprocable in said bearing and extending into 40 said chambers; meansto seal the ends of said piston from said chambers; and reciprocatingmeansincluding a cross-head, a pair of push rods connected to saidcross-head, and a pair of cross bars'connected to said push rods andextending into said bearing and connected to said piston between saidsealing means.

5. A pump having a pair 01' chambers an inlet valve and an outlet valvefor each of said chambers; a bearing between said chambers; a piston 60reciprocable in said bearingland extending into said chambers; and anelastic cup-shaped member in each of said chambers, sealed to the wallof its chamber adjacent said bearing, enclosing the adjacent end of saidpiston, and being at all times taut on said piston.

55 6. A pump having a pair of chambers; an inlet valve and an outletvalve for each of said chambers; a bearing between said chambers; apiston reciprocable in said bearing and extending into said chambers;and an expansible cup-shaped member in each of said chambers, sealed tothe wall 01' its chamber adjacent said bearing, enclosing the adjacentend of said piston, and being at all times taut on said piston.

7. A pump having a pair of chambers; an inlet valve and an outlet valvefor each of said chambers; a bearing between said chambers; a pistonreciprocable in said bearing and extending into said chambers; and anelastic member in each oi! said chambers sealed to the wall of itschamber adjacent said bearing, and sealed to and enclosing a portion ofsaid piston, and being at all times taut on said piston.

8. A pump having a pairoi' chambers; an inlet valve and an outlet valvefor each of said chambers; a bearing between said chambers; a pistonreciprocable in said bearing and extending into said chambers; and anelastic member in each of said chambers and sealed to the wall of itschamber adjacent said bearing, and sealed to and enclosing'a portion ofsaid piston.

9. A pump having a chamber; an inlet valve and an outlet valve for saidchamber; a bearing adjacent one wall of said chamber; a pistonreciprocable in said bearing and extending into said chamber; asubstantially tubular elastic member having oppositely extending annularrim flanges sealed to the wall of said chamber adjacent said bearing andto said piston, said member extending over the end of said piston, andbeing at all times taut on said piston.

10. A pump having a chamber, an inlet valve and an outlet valve for saidchamber, a bearing adjacent one wall of said chamber, a pistonreciprocable in said bearingand extending into said chamber, and anelastic substantially tubular member having an external annular flangeextending first radially then axially sealed to the wall of said chamberadjacent said bearing by a complemental oppositely extending ring andcompletely enclosing the end of said piston, and being at all times tauton said piston.

11. A pump having. a chamber; an inlet valve and an outlet valve forsaid chamber; a bearing adjacent one wall of said chamber; a pistonreciprocable in said bearing and extending into said chamber; and anelastic substantially tubular member having an external annular flangeextending first radially and then axially sealed to the wall of saidchamber adjacent said hearing by a complementai oppositely extendingring and attached to and sealed to and enclosing a portion of saidpiston, said member being at all times taut on said piston.

OSCAR. KUEHNE.

